High performance co2/h2o displacement desorption sorbents and methods of making same

Abstract

The disclosure generally relates to CCS sorbents, particularly for CO 2 /H 2 O displacement desorption process. The sorbents include an aluminum oxide support that includes alkali metal salts within the support, in the form of pseudo alkali aluminate. The sorbents also include alkali metal salt impregnated on the support. The sorbents demonstrate improved CO 2 loadings and better H 2 O/CO 2 ratios, as well as improved stability. Compositions and methods of making are disclosed.

We claim: 
     
         1 . A method for preparing a CCS sorbent, comprising
 preparing a support by
 mixing a mixture comprising an aluminum compound and an aqueous solution of a first alkali metal salt to form a dough, 
 extruding the dough to form an extrudate, 
 and drying the extrudate to form the support; 
   impregnating a second alkali metal salt into the support; and   drying the impregnated support to create the sorbent.   
     
     
         2 . The method of  claim 1 , wherein the extrudate is further calcined after drying. 
     
     
         4 . The method of  claim 1 , wherein the extrudate is dried at 125-500° C. 
     
     
         5 . The method of  claim 1 , wherein the extrudate is dried at 250-350° C. 
     
     
         6 . The method of  claim 1 , wherein the aluminum compound comprises aluminum oxide, aluminum oxide hydroxide, aluminum hydroxide, boehmite, or pseudoboehmite. 
     
     
         7 . The method of  claim 1 , wherein the aluminum compound comprises aluminum oxide hydroxide, boehmite, or pseudoboehmite. 
     
     
         8 . The method of  claim 1 , wherein the first alkali metal salt comprises a potassium salt, a sodium salt, or both a potassium salt and a sodium salt. 
     
     
         9 . The method of  claim 1 , wherein the support comprises a pseudo alkali aluminate. 
     
     
         10 . The method of  claim 1 , wherein the support comprises a pseudo potassium aluminate. 
     
     
         11 . The method of  claim 1 , wherein the second alkali metal salt comprises lithium, sodium or potassium. 
     
     
         12 . The method of  claim 1 , wherein the second alkali metal salt comprises sodium or potassium. 
     
     
         13 . The method of  claim 1 , wherein the second alkali metal salt comprises sodium and potassium. 
     
     
         14 . A method for preparing a CCS sorbent, comprising impregnating a second alkali metal salt solution into a support; wherein
 the support is prepared by
 mixing an aluminum compound and an aqueous solution of a first alkali metal salt to form a dough, 
 extruding the dough to form an extrudate, 
 and drying the extrudate to form the support. 
   
     
     
         15 . The method of  claim 14 , wherein the extrudate is further calcined after drying. 
     
     
         16 . The method of  claim 14 , wherein the extrudate is dried at 125-500° C. 
     
     
         17 . The method of  claim 14 , wherein the extrudate is dried at 250-350° C. 
     
     
         18 . The method of  claim 14 , wherein the aluminum compound comprises aluminum oxide, aluminum oxide hydroxide, aluminum hydroxide, boehmite, or pseudoboehmite. 
     
     
         19 . The method of  claim 14 , wherein the aluminum compound comprises aluminum oxide hydroxide, boehmite, or pseudoboehmite. 
     
     
         20 . The method of  claim 14 , wherein the first alkali metal salt comprises a potassium salt, a sodium salt, or both a potassium salt and a sodium salt. 
     
     
         21 . The method of  claim 14 , wherein the support comprises a pseudo alkali aluminate. 
     
     
         22 . The method of  claim 14 , wherein the support comprises a pseudo potassium aluminate. 
     
     
         23 . The method of  claim 14 , wherein the second alkali metal salt comprises lithium, sodium or potassium. 
     
     
         24 . The method of  claim 14 , wherein the second alkali metal salt comprises sodium or potassium. 
     
     
         25 . The method of  claim 14 , wherein the second alkali metal salt comprises sodium and potassium. 
     
     
         26 . A CCS sorbent, comprising
 a support comprising an aluminum compound and a pseudo alkali aluminate, and   an impregnated alkali salt, wherein,   the alkali composition of the support is at least about 3 wt % as M 2 O, and   the impregnated alkali salt is at least about 5 wt % as M 2 O of the total sorbent.   
     
     
         27 . The sorbent of  claim 26 , wherein the pseudo alkali aluminate comprises potassium, sodium or both potassium and sodium. 
     
     
         28 . The sorbent of  claim 26 , wherein the pseudo alkali aluminate comprises potassium and sodium. 
     
     
         29 . The sorbent of  claim 26 , wherein the impregnated alkali salt comprises potassium, sodium or both potassium and sodium. 
     
     
         30 . The sorbent of  claim 26 , wherein the impregnated alkali salt comprises potassium and sodium. 
     
     
         31 . The sorbent of  claim 26 , wherein the alkali composition of the support is at least about 8 wt % as M 2 O. 
     
     
         32 . The sorbent of  claim 26 , wherein the impregnated alkali salt is at least about 9 wt % as M 2 O.